A modern digital High Frequency Receiver to explore Uranus and Neptune radio emitters

Among the known planetary magnetospheres, those of Uranus and Neptune display very similar radio environments so that they have early been referred to as ‘radio twins’. They produce a variety of electromagnetic radio waves ranging from ~0 to a few tens of MHz similar to - although more complex than - those of Saturn or the Earth (Desch et al., 1991, Zarka et al., 1995). These include the well known Uranian/Neptunian Kilometric Radiations (UKR/NKR) below 1MHz or the Uranian/Neptunian Electrostatic Discharges (UED/NED) beyond, which remain only known from Voyager 2 radio observations. Here, we present a modern concept of digital High Frequency Receiver (HFR) within the frame of a general Radio and Plasma Wave (RPW) experiment retained in various mission concepts toward Uranus and Neptune (e.g. Hess et al., 2010 ; Arridge et al., 2011, 2013, 2014 Christophe et al., 2011; Masters et al., 2013; Hofstadter at al., 2019). The presented HFR concept, based on the heritage of Cassini/RPWS/HFR, Bepi-Clompobo/PWI/Sorbet, Solar Orbiter/RPW and JUICE/RPWI/JENRAGE is aimed at providing a light, robust, low-consumption versatile instrument capable of goniopolarimetric and waveform measurements from a few kHz to ~20MHz, devoted to the study of auroral and atmospheric radio and plasma waves or dust impacts.